Precisions nouvelles sur les terrains metamorphiques du mont Pilat (Massif central) et leur histoire cristallogenetique

1964 ◽  
Vol S7-VI (1) ◽  
pp. 55-63 ◽  
Author(s):  
Maurice Chenevoy
Keyword(s):  
Chemical Composition ◽  
Contact Metamorphism ◽  
Metamorphic Rocks ◽  
Shearing Stress ◽  
The South ◽  
Mountain Area ◽  
Massif Central

Abstract Metamorphic rocks of the Pilat mountain area of the Central Massif near St. Etienne exhibit three periods of metamorphic effects involving anomalies. Period I, the oldest, is represented by mesozonal gneiss and schist (amphibolite-almandine facies) cropping out along the NW side of the area. They are part of the pre-Hercynian metamorphics of the south flank of the Lyonnais mountains. Period II involved epizonal retromorphism and recrystallization. These rocks crop out in a belt along the SE margin of the Period II series. Period III involved thermal, and probably contact metamorphism, resulting in zonation of a belt with chlorite, biotite, cordierite, andalusite, and sillimanite zones in succession SE to the Pilat mountain granite. Period III probably is younger than II. The chemical composition of the granite is anomalous. This may be the metamorphism under deficient shearing stress described by Harker, or Buchan type metamorphism, as described by Read and used by Forestier to explain the schists of the upper Allier river area of the massif.

scholarly journals Uraninite, Coffinite and Ningyoite from Vein-Type Uranium Deposits of the Bohemian Massif (Central European Variscan Belt)

Minerals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 123 ◽  
Author(s):  
Miloš René ◽  
Zdeněk Dolníček ◽  
Jiří Sejkora ◽  
Pavel Škácha ◽  
Vladimír Šrein
Keyword(s):  
Chemical Composition ◽  
Electron Microprobe ◽  
Bohemian Massif ◽  
Uranium Deposit ◽  
Ore Deposits ◽  
Metamorphic Rocks ◽  
Uranium Deposits ◽  
Massif Central ◽  
Vein Type ◽  
Ore District

Uraninite-coffinite vein-type mineralisation with significant predominance of uraninite over coffinite occurs in the Příbram, Jáchymov and Horní Slavkov ore districts and the Potůčky, Zálesí and Předbořice uranium deposits. These uranium deposits are hosted by faults that are mostly developed in low- to high-grade metamorphic rocks of the basement of the Bohemian Massif. Textural features and the chemical composition of uraninite, coffinite and ningyoite were studied using an electron microprobe. Collomorphic uraninite was the only primary uranium mineral in all deposits studied. The uraninites contained variable and elevated concentrations of PbO (1.5 wt %–5.4 wt %), CaO (0.7 wt %–8.3 wt %), and SiO2 (up to 10.0 wt %), whereas the contents of Th, Zr, REE and Y were usually below the detection limits of the electron microprobe. Coffinite usually forms by gradual coffinitization of uraninite in ore deposits and the concentration of CaO was lower than that in uraninites, varying from 0.6 wt % to 6.5 wt %. Coffinite from the Jáchymov ore district was partly enriched in Zr (up to 3.3 wt % ZrO2) and Y (up to 5.5 wt % Y2O3), and from the Potůčky uranium deposit, was distinctly enriched in P (up to 8.8 wt % P2O5), occurring in association with ningyoite. The chemical composition of ningyoite was similar to that from type locality; however, ningyoite from Potůčky was distinctly enriched in REE, containing up to 22.3 wt % REE2O3.

4. Rocks transformed

2016 ◽  
pp. 51-65
Author(s):  
Jan Zalasiewicz
Keyword(s):  
Chemical Composition ◽  
High Pressures ◽  
Regional Metamorphism ◽  
Contact Metamorphism ◽  
Metamorphic Rocks ◽  
Mountain Belt ◽  
Different Types ◽  
High Pressures And Temperatures ◽  
Contact And Impact

‘Rocks transformed’ outlines the processes of metamorphism and describes the different types of metamorphism: regional, contact, and impact. Regional metamorphism is the most common form and occurs in mountain belt zones where the crust is much thicker. High pressures and temperatures result in recrystallization in the rocks. As temperatures and pressures increase, the new crystals that form are bigger. The original chemical composition of the rocks affects the resulting metamorphic rocks. Muds become slates and mica-schists, while limestones become marbles. Contact metamorphism takes place at the boundaries of magma bodies and impact metamorphism is seen when meteorites crash into the Earth’s surface.

Composition and properties of horseradish (Armoracia rusticana), as one of the representatives of the essential oil culture in Siberia

2020 ◽  
Author(s):  
G.A. Demidenko G.A. ◽  
Keyword(s):  
Chemical Composition ◽  
Essential Oil ◽  
The South ◽  
Armoracia Rusticana

The article presents an analysis of the chemical composition and properties of horseradish (Armoracia rusticana), as one of the representatives of the essential oil culture in the Siberian conditions in the South of the Krasnoyarsk territory.

scholarly journals Research Regarding the Quality of Lambs Carcass Resulted from Tsigaia Purebred Compared with Hybrids of Tsigaia Ewes Crossed with Blanc du Massif Central Rams

2017 ◽  
Vol 74 (1) ◽  
pp. 7
Author(s):  
Mihai Marian BORZAN ◽  
Dana PUSTA ◽  
Liviu BOGDAN ◽  
Alexandra TABARAN ◽  
Attila MATE ◽  
...  
Keyword(s):  
Body Weight ◽  
Chemical Composition ◽  
Massif Central ◽  
Live Body Weight ◽  
Almost All ◽  
Qualitative Characteristics

Abstract: The research aims to compare some qualitative characteristics of purebred Tsigaia lambs and Tsigaia crossed with Blanc du Massif Central lambs. The criteria assessed were: chemical composition of purebred and Tsigaia crossed meat, the live body weight, the slaughtering performance, the weight of different carcass cut. For almost all criteria chosen the crossed individuals registered better results.

scholarly journals The distribution of stone crayfish Austropotamobius torrentium (Schrank, 1803) (Crustacea: Decapoda: Astacidae) in the south-west Romanian mountain and sub-mountain area

2010 ◽  
Vol 53 (1) ◽  
pp. 103-113 ◽  
Author(s):  
Lucian Pârvulescu ◽  
Iorgu Petrescu
Keyword(s):  
Geographical Distribution ◽  
Distribution Map ◽  
The South ◽  
Large Area ◽  
Mountain Area ◽  
South West ◽  
Austropotamobius Torrentium ◽  
Stone Crayfish ◽  
Crayfish Species ◽  
Geographical Units

The distribution of stone crayfish Austropotamobius torrentium (Schrank, 1803) (Crustacea: Decapoda: Astacidae) in the south-west Romanian mountain and sub-mountain area Data is presented in relation to the geographical distribution of the endangered crayfish species Austropotamobius torrentium. One hundred and seventy-four sampling stations situated along the streams of 15 geographical units from the South-West of Romania (Anina Mountains, Almăj, Dognecea, Godeanu, Locva, Ţarcu, Retezat, Semenic, Mehedinţi, Vâlcan, Parâng, Şureanu, Poiana Ruscă, Lipova Hills and Mehedinţi Plateau) have been investigated. A distribution map was compiled. The data from older publications were collated. The actual habitat of this species occupies a large area of South-West Romania in the mountain and sub-mountain area, being absent in the Poiana Ruscă Mts, Lipova and Dognecea Hills.

scholarly journals Magmatic and Postmagmatic Mineral Associations of the Malyutka Massif Rocks (Khudolazovkiy Complex of the South Urals)

2021 ◽  
Vol 20 (2) ◽  
pp. 99-109
Author(s):  
I.R. Rakhimov ◽  
Keyword(s):  
Chemical Composition ◽  
Crystallization Temperature ◽  
Equilibrium Temperature ◽  
South Urals ◽  
The South ◽  
Accessory Minerals ◽  
Rock Formation ◽  
Genetic Interpretation ◽  
Mineral Associations ◽  
Ore Minerals

The results of detailed mineralogical studies of the Malyutka massif altered rocks of the Khudolazovskiy differentiated complex are presented. The morphology and chemical composition of many rock-forming and accessory minerals are described. According to the study, the magmatic and post-magmatic (hydrothermal-metasomatic) stages of rock formation are distinguished. The problems associated with the genetic interpretation of a number of rock-forming and ore minerals are discussed. The conclusion about the polygenic nature of the formation of spinelids is made. The equilibrium temperature in the «Ti-magnetite–ilmenite» system (633–650 °C), as well as the crystallization temperature of chlorite, replacing phlogopite and hornblende (145–185 °C), were estimated.

Middle Bronze Age Long Distance Exchange through Europe and Beyond

2020 ◽  
Vol 26 (2) ◽  
pp. 266-274
Author(s):  
Flemming Kaul
Keyword(s):  
Chemical Composition ◽  
Bronze Age ◽  
Glass Beads ◽  
The South ◽  
Long Distance ◽  
Blue Glass ◽  
The North ◽  
Southern Scandinavia ◽  
Middle Bronze Age ◽  
The Mediterranean

Abstract The introduction of the folding stool and the single-edged razor into Southern Scandinavia, as well as the testimony of chariot use during the Nordic Bronze Age Period II (1500-1300 BC), give evidence of the transfer of ideas from the Mediterranean to the North. Recent analyses of the chemical composition of blue glass beads from well-dated Danish Bronze Age burials have revealed evidence for the opening of long distance exchange routes around 1400 BC between Egypt, Mesopotamia and South Scandinavia. When including comparative material from glass workshops in Egypt and finds of glass from Mesopotamia, it becomes clear that glass from those distant lands reached Scandinavia. The routes of exchange can be traced through Europe based on finds of amber from the North and glass from the South.

Geothermal Survey of the South-East Margin of the French Massif-Central

1980 ◽  
pp. 202-212
Author(s):  
B. Bosch ◽  
P. Degranges ◽  
J. Demange ◽  
M. Leleu ◽  
A. Marce ◽  
...  
Keyword(s):  
French Massif Central ◽  
The South ◽  
Massif Central
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